Automatic train-control system



W. K. HOWE- AUTOMATIC TRAIN CONTROL SYSTEM April'13 1 26.

Original Filed April 1, 1916 2 Sheets-Sheet 1 INVENTOR I.

BY fiTTORNE April 13 1926, 1,580,970

W. K. HOWE AUTOMATIC TRAIN CONTROL SYSTEM Original Filed April 1, 1916 2Sheets-Sheet 2 opera/ed by 0 O vvvvvwvwm FIG.

. z A TTORNEV Patented Apr, 13, 1925.

PATENT FI'CE WINTHROP K. HOWE, or ROoHEsTER, NEW YORK, ASSIGNOR ToGENERAL BAI iiwAY SIGNAL COMPANY, OF GATES, NEW YORK, A CORPORATION OFNEW YORK.

AUTOMATIC TRAIN-CONTROL Application filed April 1, 1916, Serial No.88,365. Renewed'November 23, 1925.

To all whom it may concern:

Be it known that I, WVINTHROP K. I-IOWE, a

citizen of the United States, and a resident,

of the city of Rochester, in the county of Monroe and State of New York,have invented a new and useful Automatic Train- Control System, of whichthe following is a specification.

This invention relates to systems for automatically governing themovement of railway trains.

In the practical operation oi railroads there are conditions which makeit desirable in designing an automatic train control system to providefor two kinds of control for trains, for the reason that at some partsof the railroad the purpose of the system is to prevent collisionsbetween trains on the same track, whereas, at other parts of therailroad, such as at yards, crossings and the like, the purpose of thesystem is to prevent interference or collision between trains onconverging or intersecting tracks. In one case where the trains are onthe same track, practical operating conditions seem to be satisfied if atrain is permitted to enter a portion of track which may be occupied byanother train, providing the first train proceeds slowly and cautiously;or, in other words, it is permissible for a train to pass a signalindicating stop or danger where the danger consists in the likelihood ofmeeting some other train on the same track. On the other hand, when atrain approaches a place 'where there are converging or intersectingtracks and the right of way has been given some other train, it shouldnot be possible for the first train to pass the signal at stop whichindicates this fact, otherwise said first train, even if it wereproceeding slowly and cautiously, might cross the path of another train,which relying on the proceed indication given to it, might be movingfast. The distinction between two different kinds of control which maybe termed absolute control and permissive control, has been recog nizedin railway signaling for some time and is found in signaling systems asthey are generally installed at the present day, in that so-calledpermissive signals when indicating stop or danger may be passed by anengineer after observing certain prescribed rules and regulations,whereas the so-called absolute signals indicating stop or danger locatedat portions of the track governed by an interlocking plant may not be.properly passed by an engineer without special permission. In automatictrain control systems, however, this distinction has not been observedand followed, and in gen eral in theautomatic train control systemsheretofore developed no distinction has been made between the kind ofcontrolling effect which should be produced on a train at diiierentparts of a railroad; and furthermore, the means used for communicatinginformation from the track to the train-has been of the samecharacteristics throughout the length of the railroad;

It is contemplated according to this invention to make suitableprovisions for the two kinds of control above mentioned, and one of theprincipal objects of the invention is to devise an arrangement ofdevices and controlling circuits therefor which will ef- :ficiently andreliably afford the two kinds of control'at any required places along arailroad track without requiring the use of complicated apparatus.

Another object of the invention is to'devise a system for automaticallycontrolling railway trains in which both the absolute and the permissivecontrols are accomplished by the cooperation of contact shoes carried bythe train with ramps or contact rails located al ng the track.

Another object of the invention is to an range the absolute control ofthe train which acts to bring the train to an absolute stop so that,while this absolute control will be produced eflectively and reliably,it is not likely to occur accidentally.

Another object of the invention is to make provision for automaticallydisplaying a distinctive signal on board a train when and so long asthis train moves in the di-, rection opposite to the normal direction oftrafiic, and to arrange the control of this signal such that it may beoperated by the same ramps and contact shoes which are utilized forgoverning the movement of the train.

Other objects andadvantages will appear as the description of theinvention progresses, and the novel features of the invention will beparticularly pointed out in the appended claims. a

In the accompanying drawing, wherein I have illustrated a preferredphysical embodiment of my invention, and whereinlike characters ofreference designate corresponding parts through the several views, andin which:

Fig. 1 is a diagrammatic view of the parts and controlling circuitsembodying this invention and constituting a system for automaticallycontrolling railway trains, these parts being shown more with a view tomake the functions and correlation of the parts controlling circuitsclear than with a. View to showing the exact construction andarrangement of these parts; and Fig. 2 is a diagrammatic View ofsuitabletrackway circuits for assumed conditions suitable to illustratethe features and operation of the system.

Referring to Fig. 1, 1 and 2 designate portions of the track rails of arailroad, which are supported upon ties in the'usual manner and whichare broken away for the sake of clearness. To illustrate thecharacteristics and operation of a system embodying the invention, asingle car or locomotive is shown diagrammatically in Fig. 1 ascomprising a front pair of wheels 3-8 connected by the usual axle 4E anda rear pair of wheels 5-5 connected by the axle 6, it being understoodthat the axles 4 and 5 are in practice connected by a suitable frame(not shown). Communication be tween the track'and the vehicle isobtained by suitable contact shoes and ramps; and in the particularembodiment illustrated two contact shoes S and S are carried by thevehicle on opposite sides and at opposite ends, and since theconstruction of these contact shoes is the same, a. description of onewill sufiice for both, the same reference characters being used for theparts associated with the shoe S as for those associated with the shoeS, with the distinctive exponent 1 added thereto; For simplicity eachcontact shoe is shown supported by a suitable bracket 7 assumed forsimplicity to be of insulating -material, and each contact shoecomprises a foot or contacting portion, designated S which is pivotallyconnected to the lower ends of two angle levers 8 and 9, said anglelevers being mounted upon the bracket 7 for rocking movement in avertical plane. Attached to the end of the upper arm of the angle lever9 but insulated therefrom is a contact piece 11. 'When the shoe is notin engagement with a ramp it is in the position shown in'Fig. 1, and theupper arms of the angle levers 8 and 9 extend substantiallyhorizontally. Each contact shoe is designed not only to make electricalcontact with the successive ramps with whichis engages, but also to.

sulating material, are slidably mounted in suitable supports or guides14 and 15 secured to the bracket 7. The lower end portions of the rods12 and 13 are reduced in diameter to form shoulders which strike theguides 14 and limit the downward movement of said rods. The rods 12 and13 have a tendency, due to their weight, or aided by a spring or othermeans, (not shown), to move to their lower position as shown in Fig. 1;and are arranged one above each of the upper arms of the angle levers 8-and 9 so that, as shoe S is moved lengthwise of the vehicle and upwardin one direction, one of saidrods is raised, while if the shoe is movedsimilarly in the other direction, the other rod is raised. Connected tothe rod 12 are suitable circuit controlling contact fingers, designated16, 17, 18 and 19, the contacts cooperating with said contact fingersbeing represented by arrows; and in the same way the rod 13 is providedwith two contact fingers 20 and 21.

The ramps R for cooperating with the contact shoes S and S may be of anysuitable construction and are shown as metallic members with slopingends which are mounted adjacent. to the track rails 1 and 2 uponsuitable insulating supports, it being understood that these ramps arearranged in the same plane as the contact shoes so that, when a contactshoe engages with a ramp, said shoe is moved rearwardly relatively tothe vehicle and also upwardly and one or the other of the rods 12 or 13is lifted by the angle lever 8 or 9. According to this invention it iscontemplated that the ramps in most cases will be located upon one sideof the track, which in the articular embodiment illustrated is therighthand side for the normal direction of traffic; except at the pointswhere it is desired to be able to bring the train to an absolute stop,at which points a ramp is located on each side of the track. In somecases it may be found desirable to operate trains in both directionsover a stretch of single track and this may be accomplished by placingthe ramps on each side of the track and by arranging a suitable means,automatic or manually operated, whereby a certain difi'erence ofpotential is established between the ramps on one side of the track atall times while a train is passing through the stretch in the directionopposite to thedirection of traific governed by these ramps, and wherebythe difference of potential between the respective ramps on the otherside of the track is controlled by the track circuit sections of thestretch of track according to traffic conditions in the same way as morefully explained hereinafter. 7

The trackway circuits for controlling the difference of potentialbetween the ramps and the track rails are not shown in Fig, 1,

and for simplicity it is assumed that this difference of potential isderived from a suitable alternating current generator G, to-

which is connected by wires 22 and 23 the primary of a transformer T andalso to which is connected by wires 24 and E35 the primary of atransformer T The connections between the secondaries of thetransformers T and T are the same in most respects and thesame'reference characters are used for these connections of thetransformer T as for the transformer T with the exponent 1 addedthereto. One terminal of the secondary of the transformer T is connectedby a conductor 29 to the track rail 2, and the other terminal. of saidsecondary is connected by a conductor 28, switch 26 and conductor 27 tothe ramp R. The switch 26 is arranged so that it may break connectionwith the conductor 28 and make connection with a conductor 30 lead? ingto an intermediate point in the winding of the secondary of thetransformer T When the switch 26 is in the position shown in Fig 1, adifference of potential equivalent to the entire voltage of thesecondary of the transformer T is established between the ramp R and thetrack rail 2; whereas, when the switch 26 is moved to make contact withthe conductor 30, a difference of potential equivalent to only part ofthe voltage of the secondary T is established between'said ramp and saidtrack rail. The difference of potential between the ramp R and the trackrail 1 which is derived from the entire voltage of the secondary of thetransformer T will be hereinafter termed for convenience high voltage onthe ramp R; whereas the difference of potential derived from part ofsaid secondary will be hereinafter termed low voltage on the ramp R. Theswitch 26 may also be moved out of contact with both of the conductors28 and 30, so that no difference of potential will exist between theramp R and the track rail 2,- and this condition of the ramp R willhereinafter be referred to for convenience as no voltage on the ramp.

The permissive control of the movement of the train or vehicle may beobtained by any suitable device, preferably some device or apparatuswhich acts to control the speed of the train or Vehicle rather than tocause an immediate application of the brakes. Also, the device may bemerely a signal to guide the operator of the vehicle, or it maybeanautomatic device capable of giving a delayed application of the brakes,subject to the intervention of the operator. Various kinds of speedcontrol apparatus capable of performing the functions necessary for thisinvention are well known in the art, and it is considered unnecessaryfor the purpose of a clear understanding of this invention to show anddescribe in detail such a speed control apparatus, this apparatus forconvenience and simplicity being shown conventially and'desig'nated SC.One such type of speed control apparatus is dis-closed in my priorapplication, Ser. No. 38,132,-filed July 6, 1915. The speed controlapparatus SC is controlled by a control relay K having armatures 31, 32and 33, represented according to established convention; and the controlrelay K in turn is controlled at times by an alternating current relay34 having an armature 35, the relay 34 being preferably designed to beimmune to direct current so that its operation will not be interferedwith by the sources of direct current carried on the vehicle or by thecurrent which may be used for propelling the vehicle.

F or thepurpose of explaining this inven- -tion it is assumed that thevehicle or train is equipped with pneumatic brakes of the ordinary type,which include a trainpipe designated in Fig. 1 as 120; and since theoperation and construction of the pneumatic system of brakes is wellknown, it is considered to beunnecessary for the purposes ofexplaining'thisinvention, to show and describe in detail this system ofbrakes, it being merely necessary for a clear understandingof thisinvention to'knowthat the brakes are applied on the train or'vehiclewhen the train pipe 120 is vented. It iscontemplated according to thisinvention, although the invention isin no wise restricted to such onarrangement, that the speedcbntrol apparatus SC will control the brakesand cause the so-called service application of said brakes whenever theactual speed of the vehicle exceeds a permissive speed for the vehicleat that time, and that the absolute control, consisting infbringing thevehicle to an absolute stop, isobtained by causing an emergencyapplication "of the brakes; In the particular arrangement illustrateddiagrammatically in 'Fig. 1, a suitable electrically operated valve EBcontrols communication between thetrainpipe 120 and the outside air andis constructed. so that, when deprived of its normal energizing-current,said valve will be opened to such an extent as to vent the train pipe120 sufficiently and rapidly enough to cause an emergency applicationof'the brakes.

The valve EB controllingthe emergency application of the brakes iscontrolled by a stop relay E having two armatures 36 and 37; and saidstop relay E in turn is controlled at times by a-relay 38 having anarmature 39. The relay 38 is similar to the relay 34 and is likewisepreferably designed so as to be immune to direct current.

The relays 34 and 38 have controlling circuits so as to be responsive tocurrent flowing from a rampv to a shoe, andv thence through the frame ofthe vehicle and its wheels and axle to the track rail; but in order toinsure that direct current may not find its way to the relays 34 and38from the ramps, transformers designated TS and TE for controlling therelay 84 associated with the speed control apparatus and the relay 38associated with the emergency stop appa 'atus, respectively, areinterposed in the connection between said relays 34 and 38 and thecontact shoes.

It sometimes happens in the practical operation of railroads that it isnecessary for a locomotive, motor car or entire train :to run over atrack in the direction opposite to the'normal direction of trafiic, andin such "a case the vehicle or train making this against traffic movewill generally have no signals to guide it. In order that the engineeror motorman of a train making a move against the normal direction oftrail he may be constantly reminded of the fact that his train is makingan abnormal movement, it is desirable to display before him adistinctive signal, designated in Fig. 1 as NS, which signal may be a.colored light, an illuminated sign, movable indicator or the like. Theno-signal device NS is controlled by a relay N having two separatewindings 100 and 101 and two armatures 114 and 121. The devices on thevehicle or train are supplied with current from any suitable source, asa battery F. The different conductors and electrical connections betweenthe diflerent controlling devices will not be described in detail, sincethe different circuits set up during the operation will be fullydescribed hereinafter. In describing the operation occasion will be hadat times to refer to certain circuits which have already been traced;and in order to avoid unnecessary repetition, each of the circuits as itis traced will be given a designating.

number and will thereinafter be referred to by that number. In view .of.the number of circuits involved and their peculiar func tions, it seemsexpedient to give a brief statement in tabularform of the numbers of thecircuits and their functions as follows:

Circuit number Function performed One Normally energizes the controlrelay K.

Normally energizes the speed control apparatus SC.

Partial circuit associated with the shoe S including the primary of thetransformer TS for energizing the relay 34.

Energizes the control relay K when the relay 34 is energized.

Partial circuit on the vehicle associated with the shoe S including theprimary of the transformer TS for energizing the relay 34.

Normally energizes the valve EB and is controlled by stop relay E..

control relay K is energized. Normally energizes the stop relay E whenthe shoe S is in its normal position. Normally energizes the stop relayE when the shoe S is in its normal position.

Auxiliary circuit for energizing the valve EB when the Circuit numberFunction performed Ten Partial circuit associated with shoe S andincluding the primary of the transformer TE for energizing the relay 38.Eleven. Energilzcs the stop relay E when the relay B8 is onergizeThirteen.

Before considering the arrangement of circuits along the track as shownin Fig. 2 for properly controlling the vehicle in accordance withtraffic conditions, the operation of the parts of the system on thevehicle will be considered first. Referring to Fig. 1, the parts areshown in their normal position, and disregarding for the moment themanner in which these parts are placed in their normalposition, assumethat a vehicle equipped with the parts constructed as shown in Fig. 1 isrunning over a stretchof track where it is only necessary to control thespeed of the vehicle.

Operation of the speed control apparatus.

When the parts are in their normal position the control relay K isenergized by current supplied from the local battery F on the vehicle bya circuit which may be traced as follows:

Uz'z'cuz't Number One.

'the speed control apparatus SO which, ac-

cording to the. construction preferably employed for said speed controlapparatus, retains this apparatus in its idle condition, the circuit foraccomplishing this result being traced as follows:

Circuit N umber Two.

Commencing at the battery F, conductors 40,41, 42, 43, 52 and 53,apparatus SC, conductor 54, armature 33 of the control relay K in itsupper position, and con ductors 55, 56, 57, 58, 59 and 5l back to thebattery F.

Assume that a vehicle having its control relay K energized and its speedcontrol apparatus SO in its normal condition, approaches a ramp R on therighthand side of the track traveling inthe normal direction of trafficindicated by the arrow X. When the righthand shoe S engages the ramp Rit is swung to the left as viewed in Fig. 1 and upward, and the anglelever 3 raises the rod 12 and lifts the several contact fingers carriedby said rod, The lifting of the contact finger ,18 breaks the CircuitNumber One and thereby deprives the control relay K ofthecurrentnormally supplied to it from the battery F, so that unless the controlrelay K is supplied with current along some other circuit its armature33 will drop and set the speed control apparatus SC into operation. Thecontrol relay K is supplied with a substitute current by the operationof parts and controlling circuits as follows:

When the shoe S is operated, the contact finger 19 is raised andcompletes a partial circuit terminating at the shoe S and the axle 6 andincluding the primary of the transformer TS, said circuit being tracedas follows:

Oircm't N umber Three.

Commencingat the shoe S, conductors 60 and 61, contact finger 19 in itsupper closed position, conductors 62 and 63, primary of the transformerTS, and conductors 64 and to the axle 6.

When alternating, current flows in the primary of the transformer TSalternating current is induced in the secondary of said transformer, aswill be apparent to those skilled in the art, and thisinduced currentflows alongconductors 66 and 67 through the relay 34. The relay .34 isconstructed so that it is responsive to currents of differentintensities; but since relays capable of performing this function arewell known in the art, it is/deemed unnecessary to illustrate anddescribe in detail the construction of the relay 34. If the switch 26 isin the position shown in Fig. 1 and the entire voltage of the secondaryof the trans former T is established across the ramp R and the trackrail 2, the currentflowing in the primary of the transformer TS inducessufficient current in the secondary of said transformerto energize therelay 34 sufiiciently to raise its armature 35 from its lower position.If the switch 26 is in con tact with the conductor 30, however, so thatonly a medium voltage exists between the ramp R and the track rail 2,the current supplied to the relay 34 is not sufficient to raise thearmature 35 from its lower position, but is sufiicient to hold saidarmature in. its upper position if it is already there. Obviously, ifthe switch 26 is disconnected from both wires 28 and 30 and no currentis supplied to therelay 34, the armature 35 of said relay will remain inits lower position.

From the foregoing it can beseen that the armature 35 of the relay '34may be raised, held in its upper position if it is already there, or notraised, accordingto. theintensity of the difference of potentialexisting betweenthe ramp R and the track rail 2. The manner in whichthese differentvoltagesare supplied to the ramps in accordance withtraflic conditions will be pointed out more fully hereinafter inconnection with the. description of the trackway. circuits shown inFig'.2. I

hen-the armature 35 of the relay 34 is in its upper position, thecontrol relay K is en ergized by a circuit traced as follows:

Circuit Nmnber Four.

Commencing at the battery F, conductors 40, 41, 42, 43 and 44, controlrelay K, conductors 45 and 68, armature 35 of the relay 34 in its upperposition, and conductors 69, 58, 59 and 51 back to the battery F.

In this way, when the shoe S engages the ramp R to which high voltage issupplied, the control. relay K is maintained in its energized condition,and continues to be energized, although the voltage on the ramp R islaterreduced to the medium voltage, since this mediuinvoltage issufficient to hold the armature 35 of the relay 34 in its upper positionafter it has once been placed there. Likewise, if the control relay K isdeenergized at the time the shoe S engages a ramp R having a highvoltage supplied thereto, the control relay- K will be energized torestore the parts of the speed control apparatus to their idlecondition; and said control relay will remain energized even though thevoltage is later reduced to themedium volt age. When the high voltage onthe ramp R is later reduced to no voltage while the con tact shoe Sengages said ramp, the control relay K is deenergized and the speedcontrol apparatus set into operation; and if there is medium voltage orno voltage on the ramp R when the contact shoe S first engages saidramp, the control relay IQ will be deenergized or will remaindeenergized as the case may be The armature '31 'of the control relay Kis included inthe Circuit Number One for normally energizing saidcontrol relay, so that after this control relay has become deenergized,this armature 31 drops and prevents the re-establishment of the CircuitNumber One by the movement of the contactfinger 18 back to itslowerposition as the result of theshoe S leaving engagement with theramp R.

It may happen that the locomotive or motor car equipped with the systemshown in Fig. 1 may be turned around on the track with its other endforemost, that is, be headed in an opposite direction from that shown inFig. 1, andbe traveling at the same time in the normal direction oftraflic indicatedby the arrow X. In this case, the shoe S would becomethe righthand shoe and would engage with the'ramp R on the right-handside of the track; and this en gagement would serve to swing the shoe Sto the right, as viewed in Fig. 1, to lift the righthand rod 12 andraise the contact finger 18 thereby interrupting the Circuit Number Onein. the same ,way as the operation of the shoe S interrupts saidcircuit. Likewise, when the rod 12 of the shoe S is raised and thecontact fingerl9 is in its upper position, a partial circuitis'established between the shoe S and the axle 6 and including theprimary of the transformer TS, which circuit is similar to the CircuitNumber Three hereinbeforo traced, and may be traced as follows 2'Circuit Number Fire.

Commencing at the shoe S conductors and 71, contact finger 19 in itsupper position, conductors 72 and 63, primary of the transformer TS, andconductors 64 and 65 to 1tihe axle 6.

' rom the foregoing it is apparent that the shoe S can be used toaccomplish the same controlling functions as the shoe S if thelocomotive or motorcar is headed in the other direction and is travelingin the normal direction of traffic.

Operation 0/ the absolute stop mechanism.

When the parts are in their normal position as shown in Fig. 1, thevalve EB controlling the emergency application of the brakes is normallyenergized by a circuit traced as follows:

Circuit Number I came Number Seven.

Commencing at the battery F, conductors 4-0 and 7 3, valve EB,conductors 74 and 7 8, armature 32' of the control relay K in its upperposition, and conductors 56, 57, 58, 59 and 51 back to the battery F.

The stop relay E is normally energized when the shoe S in its normalposition by a circuit traced as follows:

Circuit Number Eight.

Commencing at the battery F. conductors 40, 41 and 79, stop relay E,Conductors and 81, armature 36 of relay E inits upper position,conductors 82 and 83, contact piece 11 closed, and conductors" 84,85,57,58, 59 and 51 back to the battery F. i

In a similar way the stop relay E is ener gized when the shoe S is inits normal posi tion by a circuit traced as follows:

Circuit Number Nine.

Commencing at the battery F, conductors 40, 41 and 79, stop relay E,conductors 80 and 81, armature 36 of the relay E in its upper position,conductors 82 and 86, contact piece ll 'closed, and conductors87, 85,57, 58. 59 and 51 back to the battery F.

It can be seen from the two circuits last traced that the stop relay Eis energized wheneither of the shoes S or S is in its normal positionand is deprived ofcurrent only when both of said shoes are operated.When both of the shoes'S and S are operatedand the stop relay E isdeprived of current along Circuits Numbers Eight and Nine, said relay Emay be maintained energized by supplying a substitute current thereto byenergizing the relay 38 and raising its armature 39. The relay 38 isenergized when current is supplied to the primary of the transformer TE,and said primary .of the transformer TE issupplied with current when ashoe on the lefthand side of the vehicle engages an energized ramp onthe lefthand side of the track as regards the direction of movement ofthe vehicle. That is, assuming the vehicle to be traveling in the normaldirection of traiiic indicated by the arrow X and that the lefthand shoeS engages the-lefthand ramp R when the switch 26 is in contact with theconductor 30 and a medium difference of potential exists between theramp R and the track rail 1. Under these circumstances the shoe S is,swung to the left, as viewed in Fig. 1, the rod 13 is lifted and thecontact finger 21 is raised, thereby establishing a partial circuitincluding the shoe S and the primaryv of the transformer TE and the axle6, said partial circuit being traced as follows: i

Circuit Number Ten.

tothe stop :relay E from the batteryF along a circuit traced as follows:

Circa-it Number Eleven.

be in position to engage the lefthand ramp R hen the shoe S- becomes alefthand shoe and engages the ramp B it is swung to the right, as viewedin Fig. 1, sothat the rod 13 islifted and the contact finger 20 israised to its upper position, thereby establishing a partial circuitsimilar to the partial circuit number ten, hereinbefore traced, whichmay be traced as follows:

Uz'rmit Nmnoer Twelve.

Commencing at the shoe S, conductors and 88, contact finger 20 ini'tsvupper closed position, conductors 89 and 00, 'n'imary of thetransformer TE, and conductors 91 and to the axle 6. Q

In the particular arrangement of controlling circuits-shown in Fig. 1,the emergency application of the brakes depends-upon a previousdeenergization of the control relay K and the operation of the speedcontrol apparatus SC, followed by the concurrent en gagei'nent of theshoes S and S with ramps on each side of the track, the lefthand ramp Rhaving no voltage applied thereto and the righthand ramp R having eitherno voltage or only medium voltage applied thereto. The manner in whichthese particular conditions are produced will be pointed out hereinafterin describing the trackway circuits shown in. Fig. 2.

As pointed out hereinbefore, it is desirable to give a distinctiveindication to the engineer or motorman when his train is traveling in adirection opposite to the normal direction of traflic, and this resultis ac complished by energizingthe lie-signal relay N. Not-only shouldthe no-signal indication be given, but also suitable provision should bemade for preventing the operation of either the speed control apparatusor the emergency application of the brakes. As eX- plained hereinbefore,the speed controlling ramps are assumed to be located, except in thecase of single track, on the righthand side of the track, so that whenavehicle is making a move against the normal direction of traffic, thatis, is moving in an opposite direction to' that'indicated by the arrowX, the right-hand shoe S engages a righthand ramp R and, due to thereversed movement of the vehicle, said-shoe S ismoved to the right asviewed in Fig. 1. It is apparent that this-righthand movement of theshoe 8 does not raise! the circuit controlling rod 12, and consequently,the contact finger 18- is undisturbed and maintains the'Circuit NumberOne closed. In this way, a train may travel through a stretchof trackin, the di rection opposite to the normal direction of traffic withouthavingits speed control apparatus a-ifected-v a p a In may casesthevmovement against the normal direction of traffic originates at aninterlocking plant where there will be two ramps R and R? on each sideof the track, there being two ramps at such a place in order that theemergency brakes may be applied at such a pointitnecessary on a trainapproaching'this pointin the normal direction of traffic To permit atrain making a reverse movement against the normal direction of traffictopass these two ramps .it is necessary to supply medium voltage to therighthand ramp B so that when the shoe S engages this ramp and is.swunggto the right, the partial Circuit Number Twelve includ ing, theprimary of the transformer TE, is established, thereby permitting themedium voltage on the ramp R to maintain the, stop relay Eenergizedthrough Ineansofthe relay 38 and Circuit Number Eleven.

hen a train making a movement against the normaldirection oftraffic-passes the two ramps at an interlocking, plant, the rampcorresponding, to the ramp, R and which is on the lefthand side. of thetrack as regards the normal direction of traffic but is on the righthandside as regards the direcand when the other shoe S is in its normalposition, since under these conditions the shoe S will be swung to theright as viewed in Fig. 1, and the contact finger 21 raised to close acircuit as follows:

Circuit Name-oer Thirteen.

Commencing at the battery F, conductors 40, 41, 42, 102 and 103,"winding 100 of the relay N, conductors 104 and 105, contact finger 21in its upper closed position, conductor 106, contact finger 17 in itslower closed position, conductors 108, 107, 50 and 51 back to thebattery F.

It should. be noted that the liorsignal relay N isordinarily energizedwhen a train commences a reverse movement against traffic at a pointwhere two ramps R and R are'located, since for reasons more fullyexplained hereinafter, the shoe S, then the lefthand shoe will be inengagement with the ramp R after the shoe S then the righthand shoe, hasleft engagement with the ramp B so that the Circuit Number Thirteen maybe established.

In casethe vehicle, when making a reverse movement of the characterabove described, is headed in the other direction so that the shoes Sand S are reversed, a circuit for energizing the no-signal relay N isestablished when the shoe S is moved to the left as viewed in Fig. 1 andthe shoe S is in its normal position, said circuit being traced asfollows: V

'Oe'reuz't Number Fourteen.

Circuit Number Fifteen.

Commencing at the battery F, conductors 40, 41, 42, 102 and 112, winding,101 of the relayN, conductor 113, armature 114 of the relay N in itsupper position, conductor 115, contact finger 16 in its lower closedposition, conductor 116, contact finger 16 in its lower closed positionand conductors 117, 50 and 51 back to the battery F. 7 It can be seenthat the last traced circuit is unaffected by the successive engagementof the shoe S with the ramps B when the train is moving in a directionopposite to the normal direction of traflic, but as soon as the trainchanges its direction of movement and moves in the direction of thearrow X, the first ramp R will rock the shoe S to the lift, as viewed inFig. 1, thereby lifting the contact finger 16 to'interrupt themaintaining-or stick Circuit Number Fifteen and since neither theCircuits Numbers Thirteen and Fourteen are established at this time, theno-signalrelay 21is deenergized. In this way the no-signal relay N isautomatically energized'a'ssoon as'a train commences [a movement againstthe normal direction of traffic, and is also .deenergized as soon as thetrain assumes its movement in the normal direction of traflic.

It should be noted that. the maintaining Circuit Number Fifteen is alsointerrupted when the righthand shoe on a train traveling in thedirection opposite to the normal direction of traffic engages a ramp Ron the lefthand side of the track as regards normal direction oftraffic, but on the same side of the track as the righthand shoe of thevehicle as regards the direction of movement of said vehicle. In otherwords, assuming the vehicle shown in Fig. 1 to be traveling in thedirection opposite to that indicated by the arrow X, and that the shoe Sengages the ramp R then the shoe S will be rocked to the right, asviewed in Fig. 1, thereby raising the contact fingers 16 to interruptthe maintaining Circuit Number Fifteen for the no-signal relay. Sincethis particular condition just described can arise only when a trainmoving against the normal direction of traffic reaches a point wherethere are ramps 'on'both sides of the track governed by an interlockingplant, it is possible very shortly thereafter to reenergize theno-signal relay by establishing the Circuit Number Thirteen in the sameway as hereinbefore described.

When the no-signal relay N is energized its armature 121 in its upperposition closes a circuit for energizing the no-signal device NS asfollows:

(le'reuz't Number Sixteen.

Commencing at the battery F, conductors 40, ll, 42, 43, 52 and 118,device NS, conductor 119, armature 121, in its upper position, andconductors 122, 58, 59 and 51baclr to the battery'F.

The controlling effects produced as hereinbefore described may beconveniently placed in a tabular form as below, it being understood thatthe terms right and left mean right and left with reference to thedirection in which the vehicle or train is traveling at thetime.

Shoo position. Voltage on ramp.

Gives- Left. Right. Left. Right.

Down Up..- High followed Proceed indiby medium. cation. Down.. Up Highfollowed Caution indiby zero. cation. Down Up- Mediumorzero Permissivefollowed by step indicamedium or tion.

zero. Up..." Up--- Medium High followed Proceed indiby medium. cation.Up- Up-- Medium High followed Caution indiby zero. cation. Up Up MediumMediumor zero Permissive followed by step. medium or zero. Up. Up ZeroMedium or zero. Absolutestop. Up Down. High, medium Medium Nosignalindior zero. cation.

Having described in general the construction and operation of the partsof the system carried by the vehicle or train, one arrangement ofcircuits shown in Fig. 2 for automatically controlling the voltageapplied to the ramps in accordance with traftic conditions will now bedescribed. tererring to Fig. 2, a horizontal stretch of track dividedinto blocks A, B, C and D by insulating joints 123 is shown, and it isfurther assumed that this stretch of track is intersected near itsrighthand end by another stretch, it being understood that the controlof trains, over this other stretch of track is accomplished in a similarway to that about to be described for the first mentioned or horizontalstretch. The normal direction of traffic over the horizontal stretch isindicated by the arrow X. Associated with each block and locatedpreferably at the entrance thereto are control ramps RB, RC and RD whichcorrespond to the ramp ltin Fi 1; and associated with the block D at theentrance to which the absolute stop should be given, is a ramp RD whichcorresponds to the letthand ramp R in Fig. 1. The trackway circuits arepreferably supplied with alternating current derived from a suitablealternating current generator 12% connected to the line wires 125 and126; and at the entrance to each block is located a transformer, theprimary of which is connected across said line wires, said transformersbeing designated 127, 127 and 127 for the blocks 13, C and Drespectively. The parts associated with the blocks B, C and D are inmany respects the same, and these parts which are the same, will begiven like reference characters having exponents added thereto A portion128 of the secondary of the transformer 12? is connected by conductors129 and 180 across the track rails 1 and 2 at the exit end of thepreceding block; and across the track rails 1 and 2 at the entrance endto each block a track relay 133 of suitable construction is connected byconductors 131 and. 132, said track relays having armatures 13 i and 185represented in accordance with established convention.

In addition to controlling the voltage supplied to the ramps RC, RD andE13 by the track relays oi the adjacent blocks, it is necessary tocontrol these voltages according to whether or not it is desired tobring a vehicle to an absolute stop at the end of the block C; and forthis purpose a suitable ci cuit controlling device 150 having contactfingers or switches 151, 152 and is provided, it being contemplated thatthis circuit controlling device 150 will be operated simultaneously orin connection with the usual fixed signal 0 at the entrance to the blockD. In other words, the circuit controlling device 150 may be directlycon. nected to the signal 0 and operated simultaneously with themovement of this signal, or said device may be operated in connectionwith the signal 0 by the lever or the like, controlling said signal,this signal be ing controlled in any one of the usual ways To enable aclear understanding of the traclrway circuits shown in 2, withoutentering into an unnecessarily detailed description, the circuits setupand the voltage supplied to each ramp under difierent traiiieconditions will be briefly described, and by reference to the tableherein'before given, the eii'ect produced by these oltages will beapparent. Assuming a train in the block A about to enter the block B,then before the first pair of wheels and axle of this train actuallyenter the block B, the track relay 133 will be energized so that highvoltage applied to the ramp RB by a partial circuit follows: Commencingat the ramp RB, conductors 139, armature 134: of the track relay 133, inits upper position, conductor 14:0, secondary of the transformer 12? andconductor 136 of the track rail 1. When the train in the block Aactually enters the blocl: B, the armature 13% of the track relay 133drops and connects the ramp Rt; by conductor 139 and armature 134, inits lower positionto. a conductor 141 leading ah ad to the arm ature 135of the track relay 133 of the block C, so that it the block C is notoccupied by another train a medium voltage is supplied along conductor14:2 to the ramp RB from a oortion of the secondary ot the transformer12?. However, if the block 0 is occupied, the armature 135 will be inits lower position, thereby totally disconnecting the ramp RB from anysource of current, that is, there will be zero voltage on the ramp RB.It will be apparent that, it the block B is occupied at the time a trainapproaches the entrance to this block, tne armature 13 1 of the trackrelay 133 will be in its lower position, so that either a medium orno-voltage will be supplied to the ramp RB depending upon whether or notthe block C is occupied at that time. From the foregoing in connectionwith the table and description of the operation of the parts shown inFig. 1, it can be seen that a. train in the block approaching the blockI may be allowed to proceed, be con'ipelled to reduce its speed or maybe required to enter the block B only under such conditions and such aspeed as may be desired and permitted by the particular construction ofthe speed control apparatus us Cl, depending on whether or not the blockB C is occupied.

For the next condition of traiiic to be considered, assume that thesignal 0 has been put to stop manually by the operator in the tower,because the right of way has been given to another train on the trackintersecting the block D, and under this condition the circuitcontrolling device 150 will be in the position shown in Fig. 2'. VVhen'a llll train approaches, the block C and the first contact shoe thereonengages the ramp RC, high voltage will be supplied to this ramp RC,providing the block C is not occupied at the time by a partial circuitas follows: Commencing at the ramp RC, conductor 145, armature 134 ofthe track relay 133 in its upper position, conductor 1%, secondary ofthe transformer 12'? and conductor 136. hen the train actually entersthe block C the armature 134 drops and connects the ramp RC throughconductor 148, and said armature to the conductor 145, and since theswitch 151 is assumed to be in the position shown in Fig. 2, no voltagewill be supplied to the ramp RC. In this way, the speed controlapparatus on a train can be set into operation at the time it enters theblock C, regardless of traffic conditions in the next block in advance,that is, the block D. As the train progresses and the first contact shoethereof engages the ramp RD, the speed control apparatus will continueto be effective, since the ramp RD is disconnected from any source ofcurrent by reason of the fact that the switch 153 18 open; and,consequently,

the train may pull up to the signal 0 at the limited. speed and underthe restriction imposed upon it by the speed control apparatus. In orderto permit the vehicle to pull up to the signal 0, and also to permit acontact shoe of said train to be on the ramp RD, for the reasonhereinafter pointed out, the ramp RD is so located that the firstlefthand shoe does not engage this ramp until after the righthand shoehas engaged the ramp RD. If the train attempts to pass the signal 0,however, the lefthand shoe will engage the lefthand ramp RD, which hasno voltage applied thereto, because the switch 152 is open; and,consequently, all of the conditions necessary for the emergencyapplication of the brakes are present; that is, the control relay K isdeenergized, both a righthand and a lefthand shoe are swung rearwardly,and there is no voltage on the lefthand ramp.

After traffic has cleared and the signal 0 and the circuit controllingdevice are placed in position to permit the train to proceed, highvoltage will be applied to the ramp RD, providing the block D is notoccupied, and this high voltage will energize the control relay in: andrestore the parts of the speed control apparatus to their idle position,since the ramps RD and RD are so located that when the train pulls up tothe signal 0, the first right hand shoe of the train is on the rann) RD.Also, the ramp RD is made shorter than the ramp RD, so that the righthand shoe of a train moving in the normal direction of trafiic indicatedby the arrow X will be on the ramp RD after the left hand shoe of thistrain has left engagement with the ramp RD, this relative length and 10-i locked signal when traveling in the normal direction of trafiie- Inorder to permit a train to pass along the horizontal stretch of tracksubject only to the control of its speed control apparatus, it is onlynecessary to shift the circuit controlling device 150 to"close theswitches operated thereby, whereupon the conductor 145 associated withthe ramp RC is connected by conductor 146 to the armature 185 of thetrack relay 133 so as to make in effect the same type of controllingcircuit as associated with the ramp RE. The closing of the switch 152connects the left hand ramp RD by means of conductors 137 and 154; tothe medium voltage tap of the secondary of the transformer 127 so that amedium voltage is found on the ramp RD for all trains passing that ramp.l V hen the switch 153 is closed the ramp RD is connected by conductors138 and 148 to the armature 134- so as to form in effect the same typeof controlling circuit as shown in connection with the ramp RB. In thisway, by closing the switches 151, 152 and 153 the controlling circuitsfor the ramps RC and RD are made the same as for the ramp RB. Is shouldbe understood that the particular arrangement of trackway circuits shownin Fig. 2 is merely illustrative and does not exhaust the possiblecombinations and modifications susceptible of use with this invention.

While the controlling devices and the con trollingcircuits therefor havebeen designed in the particular embodiment of the invention shown anddescribed so as to be operated by alternating current, it is apparentthat simple modifications, which will be obvious to those skilled in theart of railway signaling, may be made whereby direct current or someother current may be used as the operating medium. Also, it should beunderstood that the invention is in no wise limited to a particular kindof speed control apparatus, nor to a particular means for obtaining anabsolute stop; likewise, the satisfactory operation of the system is notdependent necessarily upon the use of contact shoes and contact railssince inductive devices capable of performing the same functions mightbe used. Other modifications and changes may be made in the particularconstruction of parts and arrangements of the controlling circuitstherefor shown and described, without departing from the invention andwithout modifying or changing the functions of these parts or theiroperation, and also various features may be combined with the system asshown and described without departing from the invention, as forexample, several locomotives or motor cars each equipped with the systemmay be included in the same train.

Although I have particularly described the construction or one physicalembodiment of my invention, and explained the operation and principlethereof; nevertheless, I desire to have it understood that the formselected is merely illustrative, but does not exhaust the possiblephysical embodiments of the idea of means underlying my invention.

W' hat I claim as new and desire to secure by Letters Patent of theUnited States, is:

1. in a system for automatically protecting railway trathc, incombination: a track; a vehicle adapted to travel over said track; adevice carried by said vehicle on each side thereof and capable ofmoving relatively to said vehicle in either of two directions; automatictrain control apparatus on the vehicle; a normally closed circuit formaintaining said apparatus in its idle condition; means controlled byeach device for interrupting said circuit when that device is moved inone direction relatively to the vehicle; normally open partial circuitsfor preventing the operation of said apparatus independently of saidnormally closed circuit; means operated by the movem it oi either devicein said one direction for connecting'that device to the correspondingpartial circuit; and trafiic controlled means along the track foractuating said devices and for supplying current to said partialcircuits.

2. In a system for automatically protecting railway tratlic incombination: a track; a vehicle adapted to travel over said track;automatic train control apparatus on the vehicle a partial circuit forcontrolling said apparatus; a device on the vehicle on each side thereofand capable of moving relatively to said vehicle in either of twodirections; means governed by each device for electrically connecting itto a terminal of said partial circuit when that device is moved in onedirection relatively to the vehicle; and means along the track foractuating one or the other of said devices in said last mentioneddirection when the vehicle is travelover the track in the normaldirection of tralae depending upon which end 01 the vehicle is ahead.

3. In a system for automatically protecting railway traffic incombination: a track; a vehicle adapted to travel over said track;braking means for retarding the movement of the vehicle; a relay forcontrollingsaid braking means; a circuit for normally maintaining saidrelay energized; a partial circuit rmgoverning said relay; devicescarried by the vehicle on the opposite sides thereof and each capable ofmoving relatively thereto in either of two directions; means controlledby said devices for interrupting said first mentioned circuit when bothof said devices are moved in either direction relatively to the vehicle;means governedby each device for electrically connecting that device toa terminal of said partial circuit when that device is moved in onedirection relatively to the vehicle; and means along the track forgoverning the movement of said devices.

l. In a system for automatically protecting railway tratlic, incombination: a track; a vehicle adapted to travel over said track;braking means for retarding the movement of said vehicle; a multiplecircuit for controlling said braking means said braking means being setinto operation when both of said circuits are interrupted; a relay forcontrolling each of said circuits; two inipulse receiving elementscarried by the vehicle on opposite sides thereof; mes governed by eitherimpulse element for controlling; one relay; and means responsive to themultaneous and joint influence of both impulse elements for controllingthe other relay.

5. In a system for automatically protecting railway traliic, incombination; a track; a vehicle adapted to travel over said track; adistinctive signal; and means on the vehicle and located along the trackin cooperative relation for automatically operating said signal when andas long as the vehicle travels over said track in the direction oppositeto the normal direction of trafiic.

6. In a system for automatically protecting railway traliic, incombination: a vehicle; apparatus for governing the speed of saidvehicle; mechanism for stopping said vehicle; partial circuits forseparately controlling said apparatus and said mechanism; a devicecarried by the vehicle and capable out movement relatively thereto ineither of two 1 directions; means governed by said device for connectingit to a terminal of one or the other of said partial circuits accordingto the direction of movement of said device; and means along the traclrfor moving said device selectively in one direction Or the other.

7.111 an automatic train control system in combination: a vehicle; anautomatic train control apparatus on the vehicle; a contact shoe carriedby the vehicle and co1nprising a movable element; a partial circuit onthe vehicle controlling; said apparatus; and normally open circuitcontrolling means for connecting said partial circuit to said shoe, saidmeans being operated to establish such connection when said element ismoved in one direction but not in the other direction by cooperatingdevices along the track for the vehicle.

8. In an automatic train control system for arailroad, speed controlapparatus wholly on a vehicle and having its operation conditioned fromthe t-rackway, said apparatus while operating acting to enforcepredetermined speed restrictions for the vehicle automatic stopmechanism on the vesicle for arresting the movement thereofindependently of its speed, means normally acting to prevent operationof the stop mechanism and rendered inactive when the speed controlapparatus is set into operation and impulse transmitting means co 3-prising trackvay devices and separate elements on the vehicle actin whenco-operating separately or jointly to produce distinctive controls forgoverning the speed control apparatus and the stop mechanism atpermissive and absolute control points along the track.

In an automatic train control system. con'ibinat-ion: a vehicle; speedcontrol apparatus on the vehicle for gradually controlling the movementthereof; automatic stop mechanism on the vehicle for immediatelyarresting the movement thereof; partial circuits for controllin saidapparatus and said mechanism; a c (216i? shoe carried by the vehicle andcomprising a movable elei'nont; and normally open circuit controllingmeans for selectively connecting said contact shoe to said partialcircuits when said element is moved in opposite directions, by devicesalong the track for the vehicle.

10. In an automatic train control system,

combination: a vehicle; apparatus for gradually controlling the movementof the vehicle; mechanism for bringing the vehicle to an absolute stop;duplicate impulse de viccs on opposite sides of the vehicle effectivewhen either is influenced separately to control said apparatus and wheninfluenced jointly to control said mechanism; and means for preventingthe operation of said mechanism while said apparatus is in itsnon-controlling condition.

11. In an automatic train control system, in combination: a vehicle;separate speed controlling apparatus and automatic stop mechanism on thevehicle; separate relays for controlling said apparatus and saidmechanism; partial circuits for controlling said relays; contact shoescarried by the vehicle on opposite sides thereof; ramps along the trackfor giving to the contact shoe on the corresponding side of the vehiclea predetermined movement relative to th vehicle when the vehicle travelsin the normal direction of traffic; a ramp along the track for giving tothe contact shoe on the other side of the vehicle a dill'erent movementrelatively to the vehicle when the vehicle travels in the normaldirection of traffic; and circuit controlling means associated with eachshoe and operated by the movements thereof to selectively connectthat'shoe to one or the other of said partial circuits.

12. In an automatic train control system, in combination: a vehicle anda track therefor; ashoe carried by the vehicle on each side thereof,each shoe comprising an element which is moved by the cooperation of theshoe with a ramp along the track in a direction relatively to thevehicle according to which side of the track the ramp is located andalso according to the direction of movement of the vehicle relative tothat ramp; separate automatic speed control apparatus and stop mechanismon the vehicle selectively controlled by a particular movement of theelement of either shoe and by the simultaneous movement of the shoes ineither direction; ramps located at intervals along one side of the trackfor causing said particular movement of the element of the shoe on thatside of the vehicle to control the speed control apparatus; and ramps onboth sides of the track at certain points for causing movement of theelements of both shoes and thereby controlling the stop mechanism.

13. In an automatic train control system, in combination: a railroadtrack having a control point where trains may be allowed to proceedaccording to traflic conditions at some times and should be brought toan absolute stop regardless of tratlic conditions at other times;impulse transmitting means at said control point; other impulse transmitting means at a distance in the rear of the control point; trackwaycircuits for governing the controlling condition of both of said impulsetransmitting means in accordance with trailic conditions; and manuallyoperable means for placing both impulse trans mitting means into a trainretardingcondition independently of said traclnvay circuits.

l t. in an automate train control system, in combination: a vehicle;automatic stop mechanism for bringing the vehicle to an i1umediate stop;impulse transmitting means con'iprising trackway devices and twoseparate elements on the vehicle; means tending to cause operation ofsaid mechanism when both of said elements cooperate vith corrcspondingtraclcway devices; means dependent upon the controlling condition of oneof said two traclnvay devices for preventing operation of saidmechanism; and manually operable means for governing the controlling;condition of said one trackway device.

15. In an automatic train control system, in combination: a vehicle anda track there for; speed control apparatus on the vehicle for graduallycontrolling the movement thereof; automatic stop mechanism on thevehicle for immediately arresting the movement thereof; trackway devicesand elements on the vehicle arranged in cooperative relation andconstituting means for transmitting impulses from the track to thevehicle; said traclzway de ices being arranged in a predetermined way atstopping points lit) controlling said trackway devices at speed controlpoints in ace rdance with tratiic conditions and manually cru ble meansfor govci Q the tracliway devices ll e stopping point and forsimultaneously governing the tracltway device at t e speed control pointnext in the rear of stopping point, whereby upon its approach to astopping point the movement of the vehicle Will be first graduallyregulated and then immediately arrested if the vehicle continues pastthe stopping point.

16. In an automatic train controlsystem, in combination: a vehicle and atrack thereit speed control apparatus on the vehicle tor graduallyregulating the movement thereof; automatic stop mechanism on the vehiclefor immediately arresting the moiment thereof; circuits and apparatuspartly on the vehicle and partly along the track for automaticallycontrolling the speed control armaratus in accordance with trariiccondilions; and manually operable means for controlling said circuitsand apparatus independeutly of traffic conditions to cause operation ofthe speed control apparatus and a subsequent operation of the automaticstop mechanism as the vehicle approaches and passes stopping point alongthe track.

17. In an automatic train control system, in combination: a vehicle anda track therefor divided into track circuit blocks; impulse deviceslocated at. intervals along the track to control the movement of trainsthrough the several blocks; trackvvay circuits controlled by the trackcircuits of said blocks "tor governing the controlling conditions oisaid implse devices in accordance uith tra'lnc conditions; elements onthe vehicle adapted to alternately cooperate with s l impulse devicesaccording to the way in much the vehicle is headed; an additionalimpulse device located at a point along the track where the vehicleshould be brought to an absolute stop, said additional impulse devicebeing arranged to cooperate with the elc-nienton the vehicle which isnot in posi tion to cooperate with the first mentioned in nu se devices;automatic stop mechanism on he vehicle having its operation responsiveto the controlling condition of the additional pulse device; automaticspeed controi mechanism on the vehicle havinf its oporation responsiveto the controlling conditir is of the other impulse devices; andmanually operable means for governingthe controlling condition or"- saidadditional in1- pulse device.

18. in an automatic train control system, in combination: a railroadtrack having an automatic block signal territory for permissive stopsand a point of absolute stop; ramps located at intervals along one sideof the track througl'iout the block signal territory for controlling themovement of trains through said blocks; traclnvay circuits forgoverning. the controlling condition of said ramps in accordance withtraliic conditions in said blocks; two ramps located opposite oneanother on opposite side of the track at the point of absolute stop; andmanuallyoper able "means for 'verning the controlling condition of saidtwo ramps and also the controlling condition of the ramp next in therear thereof independently of said trackway circuits.

19. In an automatic train control system, in combination; a railroadtrack having a region Where trains may be governed in accordance withtraffic conditions at some time: and be slowed down and brought to anab'solutestop at other times; impulse devices and trackway circuits forgoverning the movement of trains through said region in accordance withtraflic conditions; and manually operable means for governing saidtracltway circuits independently of trailic conditions to cause trainsto be slowed down and brought to an absolute'stop.

20. In an automatic train control system, in combination: a vehicle;impulse tranqmitting means comprising devices along the trackcooperating with elements on the vehicle; said elements being responsiveto the direction or" movement of the vehicle relative to the trackwaydevices; a normally inactive distinctive signal; means controlled bysaid elements for rendering said signal active when the vehicle travelsopposite to the normal direction oi tratlic; a circuit acting tomaintain said signal active after it has been initially rendered active;and means-controlled by said elements when the vehicle travels in thenormal direction of tratiic for controlling said resume its normalinactive condition. 7

21. In an automatic train control system, in combination: a vehicle anda track therefor; impulse transmitting devices located at circuit tocause said signal to automatically intervals along the track; impuli-ereceiving elements on the vehicle adapted to cooperate with saidtraekway devices, said elements comprising a movable member which is.moved in opposite directions according to the direct-ion ofmovemento-fthe vehicle relative to a trackway device; automatic train controlapparatus governed by the movement of said member in one direction, thismovement corresponding to the movement which is given saidm'ember whenthe vehicle travels in the normal direction of traiii and a dis incisivesignal rendered active by the movement ottsaicl member in an oppositedirection for indicating that the vehicle travelling opposite to thenorn'ial direction or traffic. p p 22. In an automatic train controlsystem;

in combination: a vehicle; automatic train control apparatus on thevehicle; a relay for controlling said apparatus; a normally closed stickcircuit for maintaining said relay energized; a partial circuit forcausing energization of the relay independently of its stick circuit; acontact shoe carried by the vehicle and comprising a niiovable element;ramps along the track adaptedto copcrate with said shoe and causemovement of its element in accordance with the direction of movement ofthe vehicle; and circuit controlling means operated by the movement ofsaid element when the vehicle is traveling in the normal direction oftraffic for simultaneously breaking said stick circuit and connectingsaid partial circuit to the shoe.

23 In an automatic train control system, in combination: a. vehicle;separate speed control apparatus and automatic stop mechanism on thevehicle; separate partial circuits for controlling said apparatus andsaid mechanism; a contact shoe carried by the vehicle and con'iprising amovable clement; ramps along the traclr for cooperating with said shoeand for causing movement of the element thereof in accordance with thedirection of movement of the vehicle relative to the ramp; and circuitcontrolling means operated by the movement of 'saidshoe for simultaneousy connecting it to said separate partial circuits.

24-. In an automatic train control s stern in combination: a vehicle anda track therefor; impulse receiving means on thevehicle comprising twoseparate elements arranged on opposite sides thereof; permissive impulsetransmitting means along the track; one or the other of said elements onthe vehicle being active to cooperate with said permissive impulsetransmitting means when the vehicle is traveling in the normal directionof tratilc according to the way in which the vehicle is headed; absoluteimpulse transmitting means located at predetermined points along thetrack; the one of said elements which is inactive when the vehicle isheaded in a. given direction being in position to cooperate with theabsolute impulse transmitting means.

25. In an automatic train control system in combination; a vehicle; at'ansformer on the vehicle having one termii l-l. of its primaryconnected to the wheels of the vehicle; contact shoes carried by thevehicle on 01% posite sides thereof and each comprising a movableelement; ramps along the track for giving to the elements of one or theother of said contact shoes apredetermined movement when the vehicletravels in the normal direction of tra l'iic; and normally open circuitcontrolling means associated with each shoe and operated by saidpredetermined movement of its element for connecting that shoe to theother terminal of the primary of said transformer; and train controlapparatus on the vehicle responsive to the flow of current in theprimary of said transformer.

26. In an automatic train control system for railroads which have blocksignal territory where permissive control may be enforced and one ormore control points in interlocking territory where absolute controlshould be enforced; in combination: trackway impulse devices along oneside of the track throughout block signal territory and controlled inaccordance with trafllc conditions; a vehicle; impulse receivingelements carried'by the vehicle on opposite sides thereof and adapted tocooperate separately with said trackway devices according to which endof the vehicle is ahead; permissive control apparatus on the vehiclecontrolled by the impulse element which is on the side of the vehiclecorresponding with said trackway devices; other similar trackway impulsedevices located on opposite sides of the track at each control point ofabsolute control so as to cooperate with both of the vehicle carriedimpulse elements; manually operable interlocked means for governing thecontrolling condition of said other trackway devices to cause them toenforce either absolute con trol or permissive control said means actingto place the next trackway device at braking distance in the rear of thecontrol point in its pemissive controlling condition whenever absolutecontrolling conditions are set up; and absolute control mechanism on thevehicle having its operation influenced by the oppositely locatedtraclnvay devices at said control points, whereby permissive control ofthe vehicle in accor lance with tratlic conditions is always obtained inthe block signal territory, and at some times past the absolute controlpoints, while at other times permissive control followed by absolutecontrol is obtained a the vehicle approaches and passes said absolutecontrol points.

27. In an automatic train control system for railroads which haveautomatic block signal territory where permissive control may beenforced and absolute control points in interlocking territory whereabsolute control of the vehicles should occur the combination with avehicle; of separate impulse receiving elements carried thereby:trackway impulse devices arranged in one way in block signal territory,and in a dif ferent way at each absolute control point so as toinfluence the impulse receiving elements on the vehicle dilferently:means for causing the controlling condition of the trackway devices inblock signal territory to be governed automatically in accordance withtraflic conditions; manually controlled means for regulating thecontrolling con;

dition of the tracltway devices at the absolute control points; andsepara permissive control and absolute control apparatus on the vehiclecontrolled selectively by the ditlerent influence produced on thevehicle carried elements by the different arrangements of trackivaydevices.

28. In an automatic tr in control sys n'i for raibva" s, thecon'ibination With a vehicle, of automatic train control. means thereforincluding absolute control mechanism and permissive control apparatus,impulse transmitting means for governing the operation of the permissivecontrol apparatus and comprising traifiic controlled tracltivay deicesand duplicate vehicle carried elements, said vehicle carr' d elementsbeing separately influenced by the traclnvay devices according to whichend of the vehicle is ahead While it is traveling in the normaldirection of traffic, and manually controlled means including; the salsavehicle carried element and similar at ditional trackivay devices forcausing operation of the absolute control mechanism at certain pointsalong the track.

29. In an ilUtOD'ltttlC train control system for railroads, thecombination with a vehicle, of automatic train control means on the\"GlllC-lG including speed control apparatus adapted when set intooperation to restrict continued progress of the vehicle to apredeterminer ininiinuu'i speed, and absolute stop mechanism adapted toapply the brakes to the vehicle regardless of its speed; duplicuteimpulse receiving elements on the vehiclo each separately effective tocontrol the opera ion of the speed control apparatus, and jointlyeffective to control the operation of the stop mechanism; and trackivayde vices tor influencing the vehicle carried elements separately orjointly at different control points along the track.

so. In an automatic train control system for railroads, thecon'ibination with a vehicle, of automatic train control means theretoradapted to entorce permissive control by regulating its speed orabsolute control by ai iplying its brakes regardless or" its speed;trackivay impulse devices along the track. some arranged on the same,and some on opp site es of the track; receiving elements cai d by thevehicle on opposite sides thereof and acaptcd'to cooperate with atracknciv device on the corresponding side of the track, thereljiytransferrino controh ling); influences "from the trac-kivay to thevehicle: and control means on the vehicle for causing; its automatictrain control means to be governed in one way by tracltivay devices none side of the track r irds the direction of moven'icnt of the vehicle,in a dil terent Way by traclzu'ay devices on the op posits side ot thetrack, and in a still dif- C. en'ective by diii erent arrangements oftrack- Way impulse devices to enforce either pernrss ve or absolutecontrol While the vehicle is avcling in the normal direction of traitic,and also permit the vehicle to travel opposite to the normal directionof trailio ivithou t being stopped.

31. in an automatic train control system to: railroads, the combinationWith a vehicle, ot autoi'natic train control means therefor adapted toe1 orce either permiscontrol by regg'ulatine the speed otthe L) vehicleor absolute control by applying the brakes regardless of speed, impulsereceiving elements on the vehicle adapted to be influenced by traclnvaycircuits and devices in diil'et'cnt Ways to eiiitinice either thepermissive or the absolute control, trackn'ay devices for cooperatingwith said impulse receiving elements, and arranged differently at thevarious control points along the track to produce the permissive controlor absolute control required, means for controlling the t-rackivaydevices at permissive control points in accordance with trailicconditions in advance, and manually operable means for governing thedevices at ab solute control points according to transient dangerousconditions.

32, l-ln autoi'natic train control system to railroads capable of r'ulatinp; the speed 0 vehicles so as to enforce permissive control, orapply the brakes on the vehicles rcgardless of speed so as to enforceabsolute control, or permitting the vehicles to pro coed opposite to thenormal direction of traliic Without being stopped, said systemcomprising, in combination: impulse devices along the track adapted tocommunicate controlling influences to each passing vehiole; separatepermissive and absolute train control apparatus carried by each vehicle;and impulse receiving elements on the vehicle tor coiritrolling saidapparatus selectively, said receiving elements beii influencedditi'erently by ditto-rent arran inents of rently euchway devices, andalso did by the same arrangement according to the direction or"movementof the vehicle th ereby- In an automatic train. control systemfor railroads, the combination with a vehicle; of automatic traincontrol means therefor; impulse receiving? elements carried by thevehicle on both sides thereof near opposite ends; impulse devices along'the track, some of said impulse devices at certain control points beingarranged to cooperate s aratcly with the corresponding vehicle c riedelement, and others at dili erent control points being arranged tocooperate simultaneously in pairs Wih both of said elements;

and control means on the vehicle influenced by the cooperation of thevehicle carried ele ments with the ti'ackway devices for governing saidtrain control means in different ways depending upon whether one or bothof said elements are influenced.

In an automatic train control system for railroads, in combination: avehicle; speed control apparatus on the vehicle; stop mechanism on thevehicle for applying the brakes thereof regardless of the speed; impulsereceiving elements carried by the vehicle on both sides thereof; impulsedevices along the track, some arranged on one side oi the track tocooperate separately with the. corresponding receiving elements, andothers at certain absolute control points arranged to cooperatesimultaneously with both of the receiving elements; control means on thevehicle influenced by the cooperation of said vehicle carried elementswith the trackway devices and adapted to control the speed controlapparatus when, said elements are influenced separately, and the stopmechanism when said elements are influenced simultaneously; and meansfor preventing operation of the stop mechanism unless the speed controlapparatus is acting.

In an automatic train control system for railroads, the combination witha vehicle, of automatic train control means therefor adapted to enforceeither permissive control by regulating the speed of the vehicle, orabsolute control by applying the brakes regardless of speed; duplicatetrackway devices at control points along the track in interlockingterritory where either permissive or absolute control should beenforced; manually controlled means for selectively placing saidtrackway devices under the control of tratlic conditions in advance, orin condition to exert absolute control on a passing vehicle irrespectiveof traffic conditions; and control means on the vehicle responsive tothe influence of said trackway devices in their different controllingconditions for governing the train control means on the vehicleaccordingly.

36. In an automatic train control system for railroads having a regionwhere trains may be governed in accordance with traffic conditions atsome times and should be slowed down and brought to an absolute stop atother times, in combination: impulse devices located on opposite sidesof the track at the point or" absolute stop; another impulse device atbraking distance in the-rear of said first mentioned device; trackwaycircuits for governing the controlling conditions of all of said devicesin accordance with traffic conditions in advance thereof; and manuallycontrolled means for modifying the controlling condition of said impulsedevices independently of said trackway circuits, thereby causing thevehicle to be slowed down and then stopped as it approaches and passesthe point of absolute stop.

37. In an automatic train control system to a predetermined minimumspeed, absolute stop mechanism adapted to apply the brakes to thevehicle regardless 01" its speed, and a normally inactive distinctivesignal for indicating that the vehicle is proceeding without theprotection of its train control means; duplicate impulse receivingelements on the vehicle disposed on opposite sides thereof; traclrwayimpulse devices along the track arranged to influence the vehiclecarried elements separately at some points, and simultaneously atothers; means acting when the vehicle car ied elements are influencedseparately for controlling the operation of the speed control apparatusand the distinctive signal alternatively, depending upon the directionof movement of the vehicle over the track; and means acting when thevehicle carried element-s are influenced jointly for controlling theoperation or" the'stop mechanism; whereby the same elements on thevehicle are made effective by different arrangements oi trackway devicesto control the speed control apparatus, the distinctive signal, and thestop mechanism.

38. In an automatic train control system for railroads, in combination:a vehicle; automatic train control apparatus on the ve hicle; adistinctive signal for indicating that the vehicle is traveling withoutthe protection of its train control apparatus; impulse transmittingmeans comprising impulse receiving elements on the vehicle arranged tocooperate with trafiic controlled impulse devices along the track, saidreceiving elements on the vehicle being influenced in one way by thetrackway devices while the vehicle is traveling in the normal directionof trailic regardless of which end of the vehicle is ahead, and in adiflt'erent way when the vehicle travels 0pposite to the normaldirection of tratiic; and means responding to the different ways inwhich said receiving elements are influenced for governing saidapparatus and signal selectively, whereby the alternative use of thetrain control apparatus and distinctive signal are automaticallydetermined according to the direction of movement of the vehicle.

39. In an automatic train control system for ralroads, in combination; arailroad track; impulse devices disposed along the righthand side of thetrack as regards the normal direction of traliic at certain controlpoints, and on both sides of the track in overlapping staggered relationat other control points; a vehicle; impulse receiving elements carriedby the vehicle on opposite sides thereof; a relay on the vehicle;control means responsive to the cooperation of said elements withcorresponding traclrway devices for governing said relay, said co trolmeans acting to energize the relay when a receiving element on theletthand side of the vehicle as regards its direction of movementcooperates with a trackway device and the righthand element is notaffected, said control means also acting to maintain the relay energizeduntil a righthand receiving element cooperates with a correspondingtrackway device, whereby the relay will be energized whenever thevehicle travels opposite to the normal direction of tratlic and will bemaintained energized until the vehicle again travels in the normaldirection of trafiic.

40. In an automatic train control system for railroadsdivided intoblocks each provided with a normally closed track circuit, impulsedevices along the track some on one side and some on the other side ofthe center line of the track and at the same distance therefrom, meanscontrolled by th track circuits for governing the controlling condi tionof the impulse devices on one side or the track to conform with traiiicconditions in advance, manually controlled means tor governing theimpulse devices on the other side of the track, and automatic train control equipment on a vehicle influenced distinctively by said impulsedevices depending upon their location.

41. In an automatic train control system, in combination: a railroadtrack; impulse devices located at intervals along one side of the track;a vehicle; a distinctive signal on the vehicle; impulse receivingelements carried by the vehicle on opposite sides thereof and adapted tocooperate separately with the track vay devices according to which endof the vehicle is ahead; and means controlled by either receivingelement on the vehicle for causing operation of the distinctive signalwhen the vehicle travels over the track in one direction opposite to thenormal direction of traffic.

4.2. In an automatic train control system for railroads having a pointor" absolute control, stopping means partly on the vehicle and partlyalong the track at said point of absolute control adapted to becontrolled manually and operable to immediately arrest the movement Offthe vehicle, a traclrway impulse device located at braking distance inthe rear of said absolute control point, speed control ap aratus on thevehicle adapted to be governed by said device, and trackway circ andcontrol means therefor acting to give a proceed or cautionarycontrolling condition of said impulse device depending upon trafiicconditions in advance, said traclrway circuits being automaticallychanged to give cautionary control when said stopping means is madeactive.

43. In an automatic train control system for railroads having tracksdivided into blocks each having a normally closed track circuit, impulsedevices located at intervals along the track at one side of the centerline thereof and controlled by certain track circuits in advance,impulse receiving elements on opposite sides of the vehicle which areresponsive to the direction of movement of the vehicle with respect to atrackway de vice, train control means on the vehicle adapted to becontrolled by the impulse receiving elements on either side of thevehicle when the respective element moves in one direction with respectto a trackway device and not in the other direction, whereby the vehiclewill be controlled when traveling in the normal direction of traflic andnot when moving against traffic, irrespective of which end of thevehicle is ahead; impulse devices on both sides of the track atpredetermined stopping points, and means for stopping the vehicle whenboth of the elements thereon are simultaneously influenced.

4.4. In an automatic train control system,

automatic stop mechanism on a vehicle for arresting the movement thereofregardless of its speed, a normally energized stick relay controllingsaid mechanism, two separate impulse devices on opposite sides of thevehicle adapted when influenced simultaneously to interrupt the stickcircuit of said r lay, and an independent energizing circuit for saidrelay controlled by one or the other of said impulse devices dependingon which way the vehicle is headed.

4-5. In an automatic train control system, electrically controlled brakemechanism on a vehicle adapted to arrest the movement thereofindependently of its speed, a normal-' ly closed circuit. formaintaining said brake mechanism inactive, separate impulse de vices onthe vehicle adapted when influenced simultaneously to interrupt saidcircuit, and another circuit for independently maintaining saidmechanism inactive and controlled by one of said devices.

46. In an automatic train control system for railroads having permissiveand absolute control points, train control means on the vehicleincluding permissive control apparatus and absolute stop mechanism,separate impulse receivingelements on the vehicle, traclrway impulsemeans arranged to influence one of the vehicle-carried elements atpermissive control points and both at absolute control points, saidvehicle-carried elements when thus influenced separately or jointlyacting to control selectively the permis's'ive control apparatus or theabsolute stop mechanism, means including track circuits for normallygoverning said trackway means, and manually operable means forindependently governing said trackway means at absolute control points.

47. In an automatic train control system for railroads having a controlpoint in interlocking territory. where trains should be brought to anabsolute stop, impulse transmitting means adapted to exert controllinginfluences on passing trains at braking distance in the rear of saidcontrol point, trackway circuits for governing the controlling conditionof said means in accordance with traffic conditions, means effective toprevent movement of trains by the absolute control point, and manuallyoperable means for controlling said last mentioned means and for placingsaid impulse transmitting means in a train retarding conditionindependently of traffic conditions.

.48. In an automatic train control system for railroads having a controlpoint in'interlocking territory where, trains should be brought to anabsolute stop, train control apparatus on a vehicle, means partly on thevehicle and partly along the track adapted to cause operation of saidapparatus at braking distance-in the rear of said control point and toprevent movement of the vehicle past said control point regardless ofits speed, and manually operable means for controlling said means.

49. In an automatic train control system for railroads having a controlpoint in interlocking territory where trains should be brought to anabsolute stop, automatic speed regulating apparatus on a vehicle,trackway means at braking distance in the rear of said control point andnormally active to set the apparatus on the vehicle into operation,normally active means at said control point for preventing movement ofthe vehicle thereby regardless of its speed, and manually operable meansfor controlling both of said means.

50. In an automatic train control system for railroads havinga normaldirection of traffic, the combination with a vehicle equipped forautomatic control of its movement, of a distinctive signal thereonindicating that it is running without the protec tion of its automatictrain control equipment, a stick relay controlling said signal, andmeans for energizing and deenergizing said relay automatically as thevehicle runs with or against traffic.

'51. In an automatic train control system for railroads having a normaldirection of traffic, the combination with a vehicle, of a normally'deenergized stick relay thereon, and means partly on the vehicle andpartly along the track for deenergizing and energizing said relay as thevehicle travels with and against the normal direction of trafficrespectively.

52. In an automatic train control system for railroads having a normaldirection of trafiic, the combination with a vehicle, of a normallydeenergized stick relay thereon, impulse elements on the vehiclecooperating with trackway means and effective to break the stick circuitof said relay when the vehicle travels in the normal direction oftraffic.

53. In an automatic train control system for railroads having a normaldirection of trafiic, the combination with a vehicle, of a normallydeenergized stick relay thereon, trackway means at one side of'thecenterline of the track, and impulse devices carried by the vehicle onopposite sides thereof and each acting when influenced by the movementof the vehicle in the normal direction of traffic with respect to atrackway means to interrupt the stick circuit for said relay.

54. In a train control system for railroads having a normal direction oftraffic, a vehicle having a distinctive signal thereon and a circuit forcontrolling said signal, an impulse element on the vehicle, and trackway devices for influencing said element, said element controlling saidcircuit when moved in a predetermined direction with respect to atrackway device, whereby the distinctive signal is automaticallycontrolled as the vehcile travels with or against traffic.

55. In atrain control system for railroads having a normal direction oftraffic, a vehicle having a train control apparatus and a distinctivesignal thereon, impulse ele-' ments on opposite sides of the vehicle,trackway means along one side of the center line of the track, thecooperation of either impulse element when on one side of the vehiclewith respect to its direction of movement acting to control saidapparatus and when on the other side to control said signal.

56. In an automatic train control system, train control apparatus on avehicle, means partly on the vehicle and partly along the track forgoverning said apparatus in accordance with traffic conditions while thevehicle is traveling in the normal direction of traffic but not whenrunning against traffic, and a stick relay on the vehicle alsocontrolled by said means and deenergized and energized automatically asthe vehicle runs with or against traffic.

57. In an automatic train control system, train control apparatus on avehicle, means including duplicate devices on opposite sides of thevehicle and cooperating trackway means for governing said apparatus inaccordance with trafiio conditions while the vehicle is running in thenormal direction

